/* 设计菜单框样式，控制整个导航菜单外观 */
.menu {
    padding: 0 0 0 32px;
    margin: 0;
    list-style: none;     /* 清除列表框默认样式 */
    height: 40px;
    background: #fff url(images/button1a.gif) repeat-x;
    position: relative;   /* 设计外框为相对定位*/
    font-family: arial, verdana, sans-serif;
    margin-top: 50px;
}

/* 以包含选择器的方式匹配每个列表项 */
.menu li.top {
    display: block;      /* 定义每个列表项以块状显示 */
    float: left;         /* 向左浮动 */
    position: relative;
}

/* 通过多层包含选择器定义选择中超链接的样式 */
.menu li a.top_link {
    display: block;   /* 设置每个超链接以块状显示 */
    float: left;      /* 向右浮动 */
    height: 40px;
    line-height: 33px;   /* 与导航栏同高 */
    color: #bbb;
    text-decoration: none;
    font-size: 11px;
    font-weight: bold;
    padding: 0 0 0 12px;
    cursor: pointer;
}

.menu li a.top_link span {
    float: left;
    font-weight: bold;
    display: block;
    padding: 0 24px 0 12px;
    height: 40px;
}

.menu li a.top_link span.down {
    float: left;
    display: block;
    padding: 0 24px 0 12px;
    height: 40px;
    background: url(images/down.gif) no-repeat right top;
}

/* 以伪类选择器方式定义鼠标经过超链接的样式 */
.menu li a.top_link:hover {
    color: #000;
    background: url(images/button4.gif) no-repeat;
}

.menu li a.top_link:hover span {
    background: url(images/button4.gif) no-repeat right top;
}

.menu li a.top_link:hover span.down {
    background: url(images/button4a.gif) no-repeat right top;
}

.menu li:hover > a.top_link {
    color: #000;
    background: url(images/button4.gif) no-repeat;
}

.menu li:hover > a.top_link span {
    background: url(images/button4.gif) no-repeat right top;
}

.menu li:hover > a.top_link span.down {
    background: url(images/button4a.gif) no-repeat right top;
}

.menu table {
    border-collapse: collapse;
    width: 0;
    height: 0;
    position: absolute;
    top: 0;
    left: 0;
}

.menu a:hover {
    visibility: visible;
}

.menu li:hover {
    position: relative;
    z-index: 200;
}

/* 以选择器分组的方式定义导航菜单中公共样式 */
.menu ul,
.menu :hover ul ul,
.menu :hover ul :hover ul ul,
.menu :hover ul :hover ul :hover ul ul,
.menu :hover ul :hover ul :hover ul :hover ul ul {
    position: absolute;
    left: -9999px;
    top: -9999px;
    width: 0;
    height: 0;
    margin: 0;
    padding: 0;
    list-style: none;
}

.menu :hover ul.sub {
    left: 2px;
    top: 40px;
    right: 2px;
    background: #fff;
    padding: 3px 0;
    border: 1px solid #999999;
    white-space: nowrap;
    width: 200px;
    height: auto;
}

.menu :hover ul.sub li {
    display: block;
    height: 20px;
    position: relative;
    float: left;
    width: 250px;
}

.menu :hover ul.sub li a {
    font-weight: normal;
    display: block;
    font-size: 11px;
    height: 20px;
    width: 192px;
    line-height: 20px;
    text-indent: 5px;
    color: #000;
    text-decoration: none;
    border: 3px solid #fff;
    border-width: 0 0 0 3px;
}

.menu :hover ul.sub li a.fly {
    background: #fff url(images/arrow.gif) 80px 7px no-repeat;
}

.menu :hover ul.sub li a:hover {
    background: #999999;
    color: #fff;
}

.menu :hover ul.sub li a.fly:hover {
    background: #999999 url(images/arrow_over.gif) 80px 7px no-repeat;
    color: #fff;
}

.menu :hover ul li:hover > a.fly {
    background: #999999 url(images/arrow_over.gif) 80px 7px no-repeat;
    color: #fff;
}

.menu :hover ul :hover ul,
.menu :hover ul :hover ul :hover ul,
.menu :hover ul :hover ul :hover ul :hover ul,
.menu :hover ul :hover ul :hover ul :hover ul :hover ul {
    left: 90px;
    top: -4px;
    background: #fff;
    padding: 3px 0;
    border: 1px solid 999999;
    white-space: nowrap;
    width: 93px;
    z-index: 200;
    height: auto;
}